My invention relates generally to shoe construction for human wearers and more particularly to a shoe construction for improving posture of the wearer.
Overall shoe styles vary substantially from year to year depending to a large degree, on fads begun by fashion designers. For a while most shoes are very fancy, then later the style is to be very plain. The toes may be pointed, or blunt and broad, and the heels may be high or low. One rather common characteristic, however, is that the sole of most shoes is generally parallel with the walking surface in the region of the ball and toes of the foot, and that the rearward portion of the sole is elevated by a heel. The sole element is substantially the same thickness throughout its length in such "conventional" designs. This construction, in most instances, maintains the wearer's heel elevated above the ball of the foot during standing or walking. This is in contrast to the position of the heel and ball during bare foot standing and walking.
Recently an effort has been made to modify shoe construction to improve posture by supporting the foot in a more natural position, i.e., as if no shoe was present. Foremost in this change is the construction described and claimed in U.S. Pat. No. 3,305,947 to Anne S. J. Kalsoy. This is widely marketed as the "Earth Shoe" and has been imitated by many manufacturers. The major drawback is the appearance because of the exterior style of the "Earth Shoe", and its competitors, departs substantially from the conventional design and is useful only for casual or informal wear. In addition, the complex shape of the sole surface in contact with the foot creates manufacturing and fitting problems for the various sizes in both women's and men's shoes.